Air conditioning apparatus



March 14, 1961 c. E. sHoLTEs 2,974,500

AIR CONDITIONING APPARATUS Filed Oct. 28. 1958 H o y 2| INVENTOR CARL E. SHoLTi-:s

Fm- .MQ/M91@ v TToR Ng Patented Mar. 14, 1961 2,974,500 AIR CONDITIONING APPARATUS Carl E. Shoites, Springfield, Mass., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Filed Oct. 28, 1958, Ser. No. 770,161

- 4 Claims. (Cl. 62-428) This invention relates to air conditioning apparatus and more particularly to apparatus for removing moisture from air by means of a refrigerating system.

The invention is particularly useful in low-cost type domestic dehumiditiers intended to be used in the cellar or basement of a private residence for maintaining acceptable humidity/ conditions within a limited area. Such units are designed for quantity manufacture, and simplicity, ease of assembly and low cost are important design considerations. This invention reduces the cost of the apparatus by employing the air cooling, or evaporator,

portion of the refrigerating system as a guard, or screen,

to prevent the user from accidentally contacting the propeller fan which circulates air through the dehumidifier. A unique and novel evaporator configuration is provided which, in addition to being effective as a fan guard, functions eiiiciently as a heat transfer unit and presents a pleasing appearance so as not to detract from the aesthetic appeal of the dehumidifier. In accordance with this invention, the evaporator for the dehumidifier is formed of a unitary length of bendable tubing, and has two superimposed, similarly shaped portions. These portions are preferably shaped as spirals, which are joined at their innermost turns. The outermost turns of these spirals respectively provide the inlet and the outlet for the evaporator. This twin spiral structure is stiffened by means of an elongated stiifening member disposed between the spirals and extending diametrically thereof.

Other features as well as the objects and advantages of the invention willbecome apparent from the following detailed description of the invention in which reference is made to the accompanying drawing wherein:

Fig. l is a vertical sectional view through a dehumidifier embodying this invention; v

Fig. 2 is a rear elevational view of the dehumidifier;

Fig. 3 is a plan View of the dehumidifier with a portion of the top broken away; and

Fig. 4 is an enlarged sectional view taken as indicated by the line lV-IV in Fig. 2 and showing a detail of the evaporator.

The dehumidifier employs a refrigerating system that includes a motor-compressor unit 11, which discharges compressed refrigerant gas into a condenser 12 through a discharge line 13. Refrigerant condensed by the condenser 12 iiows through a small bore expansion tube 14 into an evaporator, indicated generally by the reference numeral 15. Vaporous refrigerant is returned to the motor-compressor unit 11 through a suction conduit 16. The dehumidifier has an outer casing 17 which surrounds the motor-compressor unit 11, the condenser 12 and a motor-driven propeller fan 18, which is located directly behind, and adapted to draw air into the casing through, an inlet 19 provided in one of the end walls of the casing. The evaporator 15 is mounted on the outer surface of this end wall by means of brackets 20, and covers the inlet 19 so that air drawn into the casing 17 passes in contact with the evaporator 15.

The dehumidifier operates in a conventional manner,

in that air drawn over the evaporator 15 by the fan 18 is cooled, and moisture is condensed therefrom which falls into a condensate collection trough 21, which directs the condensate into a storage container or bucket (not shown) or to a suitable drain. Cooled and dehumidiiied-air issuing from the fan 18 flows around the motor-compressor unit 11 and over the condenser 12, from which items it absorbs heat, and is returned to the room in a dry condition and at a slightly elevated temperature. The left end of the casing 17 (as viewed in Fig. 1) is open to provide an air outlet for the casing.

In accordance with this invention, the evaporator 15 functions as a screen or guard to prevent accidental contact with the blades of the fan 18 by the user of the dehumidier. The air inlet 19 to the interior of the casing 17 is a single large opening of substantially the same diameter as the fan 18 and is large enough to readily permit the insertion of the hand of an adult user into the casing where injury might be iniiicted by the rapidly rotating blades of the fan 18. Unlike prior dehumidiers which employ a separate grill or perforated casing portion to guard the fan, the unique construction of the evaporator v15 here employed permits the evaporator to effectively function as such a guard. The evaporator 15 is formed of bendable refrigerant tubing, such as copper or aluminum, and has two similarly-shaped, superimposed portions. These portions of the evaporator preferably are shaped like two twin spirals 22 and 23, each of which is uniplanar. Adjacent turns in each spiral are placed sufliciently close to each other to prevent the fingers of the user from being inserted therebetween. A reverse bend 24 at the innermost turns of the spirals 22 and 23 joins the two portions of the evaporator and enables the outermost turns of the evaporator spirals to be used as a refrigerant inlet 25 and a refrigerant outlet 26, respectively, preferably located at the top of the evaporator, as shown in Figs. 2 and 3.

The evaporator 15 is stiiened and strengthened (to prevent deformation of the turns of the spirals 22 and 23) by means of an elongated stiiening member 28, which is disposed between the two spirals 22 and 23 and which extends diametrically with respect thereto and with respect to the air inlet 19. As best shown in Fig. 4, the member 28 preferably is a rod, made of steel or a similar, relatively stiff material, and has a non-metallic sleeve or coating 29 thereon. The sleeve 29 protects the rod against corrosion or deterioration as a result of contact with condensate forming on the evaporator 15. The

sleeve 29 also reduces rattling noises which might develop as a result of separation of the spirals 22 and 23. The spirals are preferably spaced apart a distance slightly less than the diameter of the rod sleeve 29, so that the member 28 can be retained in place by merely wedging it between the faces of the two spirals.

The use of the stiifening member 28 makes it possible to utilize relatively soft, easily formed, tubing for the evaporator 15, since the rigidity of the evaporator 15 (as a guard) does not depend entirely on the physical stiffness of the tubing. The member 28 can be relied upon to provide the necessary stiffness or rigidity of the guard. Diametrical disposition of the stiening member 28 with respect to the evaporator spirals 22 and 23 and the air inlet 19 is most effect-ive in preventing deformation of the inner turns of the spirals yet, as a result of its small diameter (approximately three-sixteenth inch), the member 28 does not interfere with the iiow of air across the evaporator and through inlet 19.

From the foregoing it can be appreciated that this invention provides an evaporator structure which is capable of effectively guarding the fan 18 from accidental contact by the user. The spiral configuration of the evaporator tubing presents a decorative and pleasing appearance, thus rendering the use of a separate decorative or protective grill or casing portion entirely unnecessary. The result is reduced cost of the article without impairment of its performance or appearance.

While the invention has been shown in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof.

What is claimed is:

l. In a dehumidifier, an outer casing having an air inlet and an air outlet, said air inlet being located in a wall of the casing other than the bottom wall and being open and unrestricted for the free passage of air therethrough, said inlet comprising at least one opening that is suiciently large to permit the hand of an adult person to pass therethrough, a propeller fan disposed within said casing behind said inlet, a refrigerant condenser disposed within said casing in the path of air issuing from said fan, and a refrigerant evaporator mounted on the outer surface of the wall of said casing in which said air inlet is located, said evaporator comprising two serially connected spiral coils of refrigerant tubing arranged in spaced, face-to-face relation and disposed across said inlet opening, the construction and arrangement being such that said evaporator guards said fan against accidental contact by the user.

2. In a dehumidifier, an outer casing having an air inlet and an air outlet, said air inlet being located in a wall of the casing other than the bottom Wall and being open and unrestricted for the free passage of air therethrough, said inlet comprising at least one opening that is sufficiently large to permit the hand of an adult person to pass therethrough, a propeller fan disposed within said casing directly behind said inlet, a refrigerant condenser disposed within said casing in the path of air issuing from said fan, a refrigerant evaporator mounted on the outer surface of the wall of said casing in which said air inlet is located, said evaporator comprising two similarly shaped coils of refrigerant tubing arranged in spaced, face-to-face relation and disposed across said inlet opening, and a rod-like stiffening member disposed between said coils and arranged substantially diametrically across said inlet opening, the construction and arrangement being such that said evaporator guards said fan against accidental contact by the user.

3. In a dehumidier, a casing having an air inlet and an air outlet, said air inlet comprising a circular unrestricted opening in a wall of the casing other than the bottom wall, a fan disposed within said casing for drawing air into the casing through said inlet, a refrigerant condenser disposed within said casing in the path of air flowing through the casing, and a refrigerant evaporator mounted in an exposed position on the outer surface of the wall of said casing in which said air inlet is located and covering said air inlet, said evaporator comprising a unitary length of bendable tubing formed into first and second uniplanar spirals having connected innermost turns, the outermost turns providing a refrigerant inlet and a refrigerant outlet, respectively, for the evaporator, said spirals being disposed in closely spaced face-to-face relationship.

4. `In a dehumidifier, a casing having an air inlet and an air outlet, said air inlet comprising a circular unrestricted opening in a wall of the casing other than the bottom wall, a fan disposed within said casing for drawing air into the casing through said inlet, a refrigerant condenser disposed within said casing in the path of air flowirng through the casing, Ia refrigerant evaporator mounted in an exposed position on the outer surface of `the wall of said casing in which said air inlet is located and covering said air inlet, said evaporator comprising a unitary length of bendable tubing formed into first `and second uniplanar spirals having connected innermost turns, the outermost turns providing a refrigerant inlet and a refrigerant outlet, respectively, for the evaporator, said spirals being disposed in closely spaced faceto-face relationship, and an elongated stiifening member disposed between the spirals of said evaporator and eX- tending diametrically thereof, said member being more rigid than said tubing.

References Cited in the tile of this patent UNITED STATES PATENTS 1,189,470 OBrien July 4, 1916 1,635,869 Weisz July 12, 1927 1,801,467 Uhyle Apr. 21, 1931 2,710,509 Ayling June 14, 1955 2,779,173 Wurtz Jan. 29, 1957 

